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Mosaico de cuasicristales a dos escalas de longitud en el mosaico
T Dotera1, T Oshiro1, P Ziherl2
1Department of Physics, Kinki University, 3-4-1 Kowakae, Higashi-Osaka 577-8502, Japan.
Nature
|February 4, 2014
Resumen
Los sistemas de materia blanda pueden formar cuasicristales a través de un mecanismo de ensamblaje genérico. Este estudio revela cómo las interacciones específicas de partículas y la geometría local impulsan el orden casi cristalino en materiales blandos, lo que permite nuevas aplicaciones.
Área de la Ciencia:
- Física de la materia blanda Física de la materia blanda
- Ciencia de los materiales Ciencia de los materiales.
- La cristalografía es una técnica de cristalografía.
Sus antecedentes:
- El orden cuasicristalino se ha observado en diversos sistemas de materia blanda como micelas y fundidos de polímeros.
- Se cree que el mecanismo de formación es genérico, independiente de las composiciones químicas específicas.
- La suavidad micelar es un factor clave propuesto para inducir el orden cuasicristalino.
Objetivo del estudio:
- Para explorar teóricamente el vínculo entre la suavidad micelar y el orden cuasicristalino.
- Investigar el papel de la geometría de embalaje local en la formación de cuasicristales de materia blanda.
- Identificar aplicaciones potenciales para las estructuras autoensambladas cuasicristalinas.
Principales métodos:
- Modelado teórico de discos duros bidimensionales con repulsión de hombro cuadrado tipo escalón.
- Simulación de las interacciones de partículas que imitan micelas macromoleculares blandas.
- Análisis del orden de orientación de los enlaces y los mosaicos geométricos resultantes.
Principales resultados:
- Se identificaron fases casicristalinas con orden de orientación de enlaces de 10, 12, 18 y 24 veces.
- Formación observada de mosaicos triangulares equiláteros e isósceles desde el núcleo al núcleo y los arreglos de hombro a hombro.
- Demostró que la geometría de embalaje local es crucial para generar cuasicristalinidad en la materia blanda.
Conclusiones:
- La suavidad y la geometría de embalaje local son fundamentales para la formación de cuasicristales en la materia blanda.
- Los hallazgos complementan las teorías existentes sobre la formación de cuasicristales en sistemas duros.
- Los mosaicos casi cristalinos tienen aplicaciones potenciales en áreas como la reproducción de imágenes y materiales fotónicos.
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